review_1

# review_1 - • Steady balance for CV(single inlet&...

This preview shows pages 1–4. Sign up to view the full content.

General Approach to Problem Solving • Sketch the process. Define your system. Label all known and unknown quantities. • Choose a model for the working substance. • Write down the mass balance equation. • Write down the energy balance equation. • Use specialized or combined forms as needed. Control volume or system Mass entering (1) Mass leaving (2) Q W

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Models of Working Substances Solid/ liquid Table A-3 C p = C v = C Gases Phase-change fluids refrigerants) Tables A-4 to 8 and A-11 to A-13 Mixtures (advanced) Perfect gas Pv = RT C p = constant C v = C p –R Table A-2a for C p . u = C v T, h = C p T . P and T are absolute. Ideal gas Pv = RT C p = f(T) Table A-2b,c. C v = C p –R Table A-17 to A-24 for u and h. P and T are absolute. Real gas Figures A-15 RT Pv Z v v ) P , T ( f Z actual ideal actual R R = = = c R c R P P P T T T = = P and T are absolute. = = T 0 v T 0 p dT C u dT C h This chart was inspired by Subrata Bhattacharjee, The Expert System for Thermodynamics , Prentice Hall, Upper Saddle River, NJ, 2003. ISBN 0-13-009235-5. www.thermofluids.net.
Mass Balance

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: • Steady balance for CV (single inlet & outlet) • Balance for closed system • Averaged flow out in CV m m dt dm ± ± − = out in 1 2 CV m m m m m − = − = ∆ av av av v V v A A m ± ± = = = av av Vel Vel ρ m m out in = − ± ± m m out in = − dt dm sys = m m m 1 2 sys = − = Energy Balance • Unsteady balance for CV (single inlet & outlet) • Steady balance for CV (single inlet & outlet) • Balance for closed system net , out net , in sys W Q dt dE ± ± − = net , out net , in sys W Q E − = ∆ gz 2 1 u e 2 + + = V 2 2 2 1 2 1 net , out net , in CV gz 2 h m gz 2 h m W Q dt dE ⎟ ⎟ ⎠ ⎞ ⎜ ⎜ ⎝ ⎛ + + − ⎟ ⎟ ⎠ ⎞ ⎜ ⎜ ⎝ ⎛ + + + − = V V ± ± ± ± 2 2 2 1 2 1 net , out net , in gz 2 h m gz 2 h m W Q ⎟ ⎟ ⎠ ⎞ ⎜ ⎜ ⎝ ⎛ + + − ⎟ ⎟ ⎠ ⎞ ⎜ ⎜ ⎝ ⎛ + + + − = V V ± ± ± ±...
View Full Document

{[ snackBarMessage ]}

### Page1 / 4

review_1 - • Steady balance for CV(single inlet&...

This preview shows document pages 1 - 4. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online